Field goad kick (happened last year), beautiful end over end from about 20 yards comes down directly ON TOP of crossbar, then like a basketball bounces up and then down on the crossbar again and finally rebounds back towards the field.
Attempt was called no good. I thought I read in a case book or on line that if the ball penetrates the vertical plane between the inside of the uprights and the front edge of the crossbar which is also in line with the inside edge of the endline, the kick would be good.
I was told by another member of the crew that it had to go past the crossbar and he used the example of kicks that hit the uprights and are no good. I figured that was not the time to try to explain it as I was a fill in on a well established crew and for folks who have not been in that position, it can make for a long, long game.
I probably won't see this again for another 100 years...but just in case.